JP2002173291A - Lifting machine control mechanism - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To detect a displacement in a working state of a working machine such as a telescopic arm by a detecting means provided at a key point, reflect the displacement on operation of a winch, and respond to a change in posture. Provided is a control mechanism for a lifting machine capable of setting a height. SOLUTION: A lifting work including a structure (a telescopic arm 10) capable of changing a working posture on a support, and a winch 20 for lifting and lowering a hanging tool suspended by a wire rope 26 from a distal end of the structure. At least two working posture detectors 36 and 37 (encoders and potentiometers) are provided at important points of the structure (the telescopic arm 10).
The operation data of the detectors 36 and 37 are operated by the operation unit of the controller 30 and output to the drive operation unit of the winch 20 to be suspended by the suspension tool (bucket 15) in accordance with a change in working posture. Make the height of the load constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control mechanism for a lifting machine mainly used for carrying out work such as excavation of earth and sand, and more particularly, to setting a suspended load height in response to a change in posture of the working machine. The present invention relates to a control mechanism of a lifting machine capable of performing the operation.

[0002]

2. Description of the Related Art Generally, in a hoist such as a crane having a telescopic arm, a winch is mounted on an upper revolving structure supported on a traveling body, and a wire rope is fed and wound from the winch. Is guided to the distal end of the arm, and is wound around the sheave of the suspender via the sheave at the distal end of the arm, thereby suspending the suspender from the distal end of the arm. Therefore, the distance between the end of the arm and the hanger changes depending on the expansion and contraction of the arm. In other words, when the arm contracts, the suspension length increases, and when the arm extends, the suspension length decreases.

[0003] If such a phenomenon occurs, depending on the work situation, it will hinder handling the suspended load. For example, in a case where an extending / contracting arm (boom) is kept in a horizontal state and an operation of moving a suspended load in a horizontal direction is performed, when the arm contracts, the suspended load descends and comes into contact with an object below. Fear arises. Therefore, in order to prevent the suspended load from lowering, the operator must perform the operation of winding the wire rope by the winch in accordance with the contraction of the arm. For this reason, the driver must pay close attention to the operation while driving, and if the suspension height is low, the nerves are concentrated more than necessary and mental fatigue increases. Further, when the arm is extended, there is a problem that if the suspended load rises and its movement is interrupted, excessive tension acts on the wire rope to damage the wire rope.

A prior art as means for solving such a problem is disclosed in, for example, Japanese Patent Application Laid-Open No. H11-171474. This publication discloses that a reduction-side oil chamber of a boom expansion / contraction hydraulic cylinder and a winch hydraulic motor are provided in the middle of a reduction line connecting a reduction-side oil chamber of a boom expansion / contraction hydraulic cylinder and a reduction-side port of a boom expansion / contraction switching valve. It is described that an interlocking switching valve and an interlocking pipe are provided for communicating the hoisting hydraulic motor for a winch with the reduction side port of the boom expansion / contraction switching valve.
By doing so, when performing the boom extension and contraction operation,
The effect that the boom extension / retraction operation and the winch lowering / winding operation can be linked to keep the hook suspension length substantially constant can be obtained.

[0005]

According to this prior art, it is possible to keep the hook hanging length constant by interlocking the raising and lowering of the winch with the expansion and contraction of the boom. However, for that purpose, it is necessary to make the amount of oil required for the rotation of the hydraulic motor for the winch and the reduction side oil chamber of the hydraulic cylinder for the boom extension and contraction equal. However, satisfying such conditions means that the volume of oil due to the expansion and contraction stroke of the hydraulic cylinder and the volume of oil associated with the rotation of the hydraulic motor for the winch are almost equal. Have difficulty.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and detects a displacement in a working state of a working machine such as a telescopic arm by a detecting means provided at a key point and reflects the detected displacement on the operation of a winch. An object of the present invention is to provide a control mechanism of a lifting machine capable of setting a suspended load height in response to a change in posture.

[0007]

In order to achieve the above-mentioned object, a control mechanism for a lifting machine according to the present invention includes a structure capable of changing a working posture on a support, And a winch for raising and lowering a hanging tool suspended by a wire rope from the distal end of the structure, wherein at least two detectors in a working posture are provided at key points of the structure, and the detectors Is calculated by a calculation unit of the controller, and is output to the drive unit of the winch, so that the height of the suspended load by the hanging tool can be set according to a change in working posture.

In the present invention, the work is carried out by raising and lowering a suspending device, for example, a hook, which is suspended by a wire rope, from the tip of a structure which is placed on a support and can change the working posture by driving a winch. In the meantime, when the position of the distal end of the structure is displaced from a reference position by the operation of a driver (for example, a hydraulic cylinder) that operates the structure, a displacement amount (data ) Is input to the arithmetic unit of the controller,
The output based on the calculation result in this calculation section is given to one of the hydraulic control valves for raising and lowering the winch hydraulic motor,
The winch is driven forward or reverse in real time to wind and unwind a required amount of the wire rope to hold the load (hanging tool) at a predetermined height.

According to the present invention, a change in the working posture of the structure supporting the suspended load is detected by at least two detectors, the data is operated by the controller, and the winch is driven by a command based on the operation result. Since the height position of the suspended load is automatically maintained at a predetermined height by operating the section, it can be set with high precision and can be rationally controlled without requiring many control / operation valves.

In the present invention, the structure capable of changing the working posture is a telescopic arm. As the working posture detector, an arm length detector is provided on a base arm or a movable arm attached to an arm support mechanism. It is preferable that an angle detector is provided at the position of the connection pin with the arm support mechanism. In a working machine equipped with such a telescopic arm, when the amount of movement of the telescopic arm from a reference position is detected by an arm length detector, the data is input to a calculation unit of a controller and calculated, whereby the winch is performed. By driving the telescopic arm in accordance with the amount of movement of the telescopic arm, the wire rope is extended and wound so that the height of the suspended load (hanging tool) suspended from the tip of the arm is kept constant. be able to. When the arm support mechanism is operated to move forward or backward while the telescopic arm is kept horizontal, the data of the arm length detector and the angle detector are calculated by the arithmetic unit of the controller, and the winch of the winch is calculated. If the drive is controlled, the suspended load height can be kept constant in the same manner. Therefore, if the operator performs the extension and retraction of the telescopic arm or the operation of moving the telescopic arm back and forth, the operator can follow and move the suspended load at a constant height and move it, thereby improving workability.

Further, in the present invention, the structure for changing the working posture is an articulated working machine in which an arm is connected to the end of a boom, and the base of the boom and the boom and the arm are used as the working posture detector. It is preferable that each of the connecting portions is provided with an angle detector. In this case, the angular displacement data of the boom and the arm by the angle detector provided at each joint is sent to the controller to be calculated, and the arm tip position is known based on the calculation result to control the winch driving unit. It is possible to move the suspended load while keeping the height position constant. Therefore, if the operator performs the extension and retraction of the telescopic arm or the operation of moving the telescopic arm back and forth, the operator can follow and move the suspended load at a constant height and move it, thereby improving workability.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of a control mechanism for a lifting machine according to the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing an embodiment of a crawler traveling type lifting working machine having a control mechanism for a lifting working machine according to the present invention. FIG. 2 is a schematic diagram showing a main part of the control mechanism according to the present embodiment.

FIG. 1 shows a crawler traveling type lifting machine 1 employing a control mechanism according to the present embodiment.
A telescopic arm 10 (which changes the working posture of the present invention) horizontally supported by an arm support mechanism 5 having a four-bar parallel link structure on an upper revolving structure 3 supported by a crawler traveling type lower traveling structure 2. And a bucket 1 suspended from the distal end of the telescopic arm 10.
The wire rope 26 is driven up and down by the winch 20 mounted on the rear part of the upper swing body 3 to carry out the excavated earth and sand. In this hoist, a bucket hanging frame 16 is supported at the tip of the telescopic arm 10, and the bucket 15 can be lifted and lowered smoothly via the bucket hanging frame 16 without swinging during lifting. .

The winch 20 is equipped with two units for raising and lowering the bucket and for opening and closing the bucket, and is driven by a hydraulic drive device. For convenience of description of the configuration, one winch 20 (a lifting winch) will be described. The wire rope 26 operated by the winch 20 passes through the guide sheave 17 provided at the rear end of the telescopic arm 10 from the winch drum 21, travels along the guide sheave 18 at the distal end along the arm, and suspends the bucket 15. It is stretched over. Then, the winch 20 and the telescopic arm 1
A wire rope tensioner 28 is provided between the wire rope 26 and the guide sheave 17 attached to the rear end of the wire rope 26 so that tension is always applied to the wire rope 26.

The telescopic arm 10 has a base arm 11 having a main boom 5 constituting the arm support mechanism 5.
a and the arm cylinder 5b (hydraulic cylinder). The boom 5a and the arm cylinder 5b have their base ends attached to the mounting member 4 on the upper swing body 3.
, And each tip is attached to the base arm 11.
The pin is connected to a mounting bracket 14 attached to the lower part of the bracket to form a four-node parallel link. The telescopic arm 10 has a telescopic hydraulic cylinder 13 incorporated therein, and the movable arm 12 inserted and supported in the base arm 11 is telescopically extended and contracted by the telescopic hydraulic cylinder 13 as conventionally known. Reference numeral 6 in the figure denotes an arm raising / lowering cylinder which normally supports the telescopic arm 10 while keeping it horizontal.

The winch 20 is driven by a hydraulically driven motor 22 (hereinafter referred to as a winch motor 22) and includes a clutch 23 and a brake 24. The controller 30 provided in the hydraulic drive unit
As a result, the ascending pressure control valve 31 and the descending pressure control valve 32
The lifting operation valve 34 is operated through the, and the winch motor 22 is driven to rotate forward and reverse. In addition,
An encoder 25 for detecting the number of rotations is attached to a rotating portion of the winch drum 21.

Further, an arm length detector 36 (for example, a reel-type sensor for feeding and winding a rope or a retractable type) is provided at an appropriate position on the base arm 11 of the telescopic arm 10. Encoder that measures by bringing a rotating body into contact with the arm)
Are provided so as to input the detection data to the controller 30. Also, the tip of the boom 5a in the arm support mechanism 5 and the mounting bracket 1
Arm connection angle detecting potentiometers 37 and 38 (angle detectors) are attached to both the pin connecting portion to the pin 4 and the pivot portion at the base end so that data of the angular displacement can be input to the controller 30. It has become. In addition, the arm length detector 36 is connected to the movable arm 1 if necessary.
2 may be attached. In addition, a magnetic stroke sensor may be attached to the arm telescopic cylinder to detect the arm length.

The operation of this embodiment having such a configuration will be described with reference to FIGS. 3A and 3B, which are diagrams for deriving the length of the wire rope accompanying a change in the working posture. .

First, the posture of the working machine is shown in FIG.
T₀As a result, the posture shown in FIG.
T in the changed state₀ΔT is the change from
And the boom 5a of the arm support mechanism 5 is an upper rotating body.
3 Tilt angle θ with respect to upper surface_B, The boot of the arm support mechanism
Angle θ of the telescopic arm with respect to the_A， The beginning of the telescopic arm
Length L_A2But change his posture and₀+ ΔT
Re θ_B', Θ_A', L _A2′, T₀At
Of the winch 20 and the guide sheave 17 at the rear end of the telescopic arm
The distance l is

(Equation 1) And the distance l ′ of T ₀ + ΔT is

(Equation 2) It is.

Therefore, the change ΔL in the length of the rope path from the winch 20 to the guide sheave 18 at the distal end of the telescopic arm via the guide sheave 17 can be calculated from the above equations (1) and (2). L _A2 ′ −L _A2 + 1′−l (3) As a result, to keep the height of the suspended load (in other words, the length h of the rope from the guide sheave at the tip end to the suspended load), the equation (3) is used. The winch may be unwound or wound at a speed of ΔL / ΔT.

Here, if the relationship between the operation amount of the winch elevating operation valve 34 and the unwinding and winding speed of the winch 20 is stored in the controller 30 of the hydraulic drive unit, it corresponds to ΔL / ΔT. The lifting operation valve 34 may be operated by the number of minutes. When the operator simultaneously performs the displacement of the telescopic arm 10 and the operation of the suspended load by the winch, the rotation speed of the winch 20 corresponding to the operation amount by the operation lever in the cab is matched with the displacement amount of the rope. When the lift valve 34 of the winch is operated by an operation amount corresponding to this speed (V _A ), the relative position between the guide sheave 18 at the tip of the arm and the suspended load is changed by an amount intended by the operator. Can be.

The operation for keeping the suspended load height constant will be described with reference to a flow sheet of FIG. 4 showing an operation for changing the posture of the working machine while keeping the suspended load height constant.

S1: The boom 5a of the arm support mechanism 5 of the working machine has an inclination angle θ _{B with} respect to the upper surface of the upper swing body 3, the inclination angle θ _A of the telescopic arm with respect to the boom of the arm support mechanism, and the initial length L _{A2 of the} telescopic arm. Is set in the controller 30. S2: The controller 30 detects the operation of the telescopic arm. S3: The controller 30 sets the value at the start of the operation of the work implement to T.

S4: The work machine operates to extend the telescopic arm 10, and the tilt of the boom 5a causes the arm length detector 36 and the arm support mechanism 5 to be attached to the telescopic arm 10.
Of the working machine by the potentiometers 37 and 38 attached to the upper end and the base end of the boom 5a.
+ ΔT) Each part data θ _A ′, θ _B ′, L _A2 ′ is detected, and the detected data is input to the controller 30.

S5: The detected variation data (θ _A ′, θ _B ′, L _A2 ′) of the work equipment is calculated by the calculation unit in the controller 30, and the change in the length of the wire rope accompanying the variation is calculated. Calculate the quantity ΔL.

S6: On the other hand, the operation by the winch operating lever in the operator's cab is input to the controller 30 and detected. S7: The controller 30 calculates a winch drive speed corresponding to the operation amount of the winch operation lever. S8: The calculated value of the winch drive speed calculated in step S7 is added to the wire rope length change amount ΔL accompanying the fluctuation amount calculated in step S5. If the calculated values in step S7 are not summed, step S5
Then, the process proceeds directly to the next step S9.

S9: The operating amount of the winch lifting / lowering operating valve 34 corresponding to the winch drive speed _VA corresponding to the wire rope length variation ΔL or the sum of the values calculated in step S7. Operation is performed at 30. S10: The pressure control valve 3 is operated based on the manipulated variable calculated.
The lifting operation valve 34 is operated via 1 (32).

S11: When the winch is driven and rotated, a data signal is transmitted from the attached rotation speed detecting encoder 25 to the controller. S12: The controller 30 calculates and calculates the operation amount of the lifting / lowering operation valve 34 for correcting the speed deviation between the actual speed of the winch and the driving speed _VA by the calculation. S13: The lifting operation valve 34 is further operated by the deviation correction amount calculated in step 12.

S14: Based on the detection data obtained by the detectors of each part, it is determined whether or not the work machine (the telescopic arm 10) is further operated. If it has not been operated (No), the process returns to the original position. If the operation has been performed (Yes), the process proceeds to step 15. S15: T = T + ΔT, θ _A at that time data of each part
= Θ _A ′, θ _B = θ _B ′, L _A2 = L _A2 ′, and the process returns to step S4 to repeat the operations from step S5.

According to the present embodiment, the wire rope operated by the winch 20 as the posture is changed by the operation of the actuator (hydraulic cylinder) in the working machine (the telescopic arm 10 and the arm support mechanism 5). The length of the hanging member (bucket) suspended from the tip of the arm can be automatically adjusted in real time based on displacement data detected in a portion where the length of the 26 fluctuates and in the vicinity thereof. Can be moved by position. As a result, for example, when the suspended load is moved horizontally by turning the arm, the suspended height can be maintained at a required height, so that the cargo handling work can be safely performed without coming into contact with the lower object. You can do it.

In the above description, there has been described the embodiment in which the horizontally supported telescopic arm changes its posture by its expansion and contraction and vertical movement or undulation by the support mechanism.
According to the gist of the present invention, for example, a work machine 40 having a dual undulating structure in which an arm 42 is pivotally attached to the tip of an undulating boom 41 and tilted by an arm cylinder 44 as shown in FIG. Can function similarly.

The working machine 40 has the up-and-down cylinder 4
3 and an arm 42 that is operated by an arm cylinder 44 at the distal end of the boom 41. A hanging tool is provided by a wire rope 46 via a sheave 45 provided at the distal end of the arm 42. The structure is such that the cargo handling work is carried out by suspending 47. Potentiometers 37 and 38 are attached to the bases of the arm 42 and the boom 41, respectively, as in the above-described embodiment, and the angular displacement data of each part is sent to a controller of a hydraulic drive unit (not shown) to transmit the angular displacement data. If the processing is performed in the same manner as in the case, the intended purpose can be achieved. Reference numeral 4 in the figure
8 is a winch.

Next, FIG. 6 shows a control mechanism for holding a bucket hanging frame attached to the tip of the arm in a horizontal position. In this embodiment, the telescopic arm 1
0, a mechanism for maintaining a horizontal level of a bucket hanging frame 16 pivotally supported at the tip of an arm 10 of the lifting machine provided with the arm. This bucket hanging frame 16 is
Brackets 16b projecting from the center of the frame body 16a with equal dimensions are provided on all sides (not shown) from the frame body 16a, and sheaves 19 are provided at the ends of the brackets 16b, respectively. Is supported by the pivot shaft 51 at the tip of the head. Then, the sheaves 19 arranged on the four sides of the bucket suspension frame 16 are wound from a winch installed at the rear of the working machine through the guide sheave 18 supported on the pivot 51 along the telescopic arm 10. The wire rope 26 to be hung,
It is wound around from the guide sheave 18 and via a guide sheave (not shown) attached to the frame 16a, so that the lower bucket 15 can be hung and opened and closed.

Such a bucket hanging frame 16 is arranged such that the hanging center of the bucket 15 to be hung by the wire rope 26 is located at the center of the area in which the hanging wire ropes are arranged. As shown in FIG. 6, the frame 16a is pivotally supported in such a manner that the hanging center is shifted by the radius d of the guide sheave 18 on the pivot 51 so as not to cause the swing. With such a structure, if the bucket hanging frame 16 is simply pivoted in a free state, there is usually no problem when raising and lowering the bucket. However, when the bucket is raised again and hit against the bucket hanging frame. , The rotational moment corresponding to the eccentricity acts, and the entire eccentricity tilts to make the desired bucket 1
5 cannot be moved up and down in a stable position. In this case, the bucket itself also tilts, and the work of loading the dump cannot be performed smoothly. In order to avoid such a problem, a tilt cylinder 53 is provided at the distal end of the telescopic arm 10, and its rod is connected to the frame 16a, and the tilt cylinder 53 controls the attitude of the bucket hanging frame 16. Have been to be.

In the tilt cylinder 53, a tilt angle detection signal from a tilt sensor 54 (a level sensor for detecting an angle with respect to a horizontal plane) attached to the bucket hanging frame 16 is transmitted and input to the controller 30 of the hydraulic drive unit. ,
The pressure control valve 55 or 56 is actuated by the output signal calculated by the arithmetic unit of the controller 30 to move the operation valve 57 disposed in the hydraulic circuit for supplying the tilt cylinder 53 to the bucket suspension frame 16 by a predetermined amount. In other words, the posture is controlled so that the inclination angle sensor 54 recognizes the horizontal position so that the posture is obtained. In this way, they can be kept normal and secure.

According to this embodiment, the arm 1
Even when performing an operation in which the 0 rises and falls, the tilt angle sensor 54 operates the tilt cylinder 53 to automatically maintain the posture of the bucket hanging frame 16 in a horizontal state, and a bucket (not shown). Can be suspended vertically, and the lifting work can be performed without impairing the workability.

In the above description, the case of a bucket as a hanging tool has been described, but a hook is used as the hanging tool.
Even when handling a suspended load, the same operation and effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a crawler traveling type lifting work machine having a control mechanism for a lifting work machine according to the present invention.

FIG. 2 is a schematic diagram illustrating a main part of a control mechanism according to the present embodiment.

FIGS. 3A and 3B are explanatory diagrams for deriving a length of a wire rope accompanying a change in a working posture, wherein FIG. 3A shows a state before operation and FIG. 3B shows a state after operation.

FIG. 4 is a flow sheet of an operation for changing the posture of the work machine while keeping the height of the suspended load constant.

FIG. 5 is an overall view of a working machine of a type combining an arm and a boom.

FIG. 6 is a diagram illustrating a control mechanism for holding a bucket hanging frame attached to a tip end of an arm in a horizontal posture.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Crawler traveling lifting machine 3 Upper revolving unit 5 Arm support mechanism 5a Boom 10 Telescopic arm 15 Bucket 17, 18 Guide sheave 20 Winch (lifting winch) 21 Winch drum 22 Winch motor 23 Clutch 24 Brake 25 Winch drum rotation speed Detection encoder 26 Wire rope 30 Controller 31 Ascent pressure control valve 32 Ascent pressure control valve 34 Elevating operation valve 36 Arm length detector 37, 38 Arm angle detection potentiometer 41 Boom 42 Arm 47 Hanging tool 51 Pivot shaft 53 Tilt cylinder 55, 56 Pressure control valve 57 Operating valve

Continued on the front page (72) Inventor Norijuge Muto 3-1-1 Ueno, Hirakata-shi, Osaka Inside the Komatsu Manufacturing Osaka Plant (72) Inventor Keiji Okamoto 3-1-1 Ueno, Hirakata-shi, Osaka Shares (72) Inventor Morio Doe 3-1-1, Ueno, Hirakata-shi, Osaka F-term (reference) 3F205 AA07 AC01 BA06 CA03 CB02 DA04 DA17 DA19

Claims (3)

[Claims] 1. A lifting work machine comprising: a structure capable of changing a working posture on a support; and a winch for raising and lowering a hanging tool suspended by a wire rope from a tip of the structure. At least two detectors of the working posture are provided at important points, and the data detected by the detectors are calculated by a calculating unit in the controller, and the calculated data is output to the driving unit of the winch and the hanging is performed according to a change in the working posture. Control mechanism for a lifting work machine, characterized in that the height of a suspended load by a tool can be set. 2. The structure in which the working posture can be changed is a telescopic arm. As a detector of the working posture, an arm length detector is attached to a base arm or a movable arm attached to an arm support mechanism. The control mechanism of a lifting work machine according to claim 1, wherein an angle detector is provided at a position of a connection pin with the support mechanism. 3. The structure for changing the working posture is an articulated working machine in which an arm is connected to the end of a boom, and a detector of the working posture is provided at a base of the boom and a connecting portion between the boom and the arm. The control mechanism according to claim 1, further comprising an angle detector.